Hi all sifuss here,wana ask something regarding my car:

Just installed my 4-2-1 extractor and zenden twister bullet because was recommended by them for my waja 4g18 auto tranny...

is it true we need to let the ecu re-calibrate the system again after we have changed the extractor or touch the o2 sensor?

because after install i didn't feel any different...and claimed by them need drive and let ecu re-calibrate again right?

And regarding the bullet in pic below,which side should receive exhaust gases and which one is letting it out?

the one below is smooth side...they put it as the gases out,and inlet for exhaust in is opposite it..mean quite restriction right?

And does this twister bullet really suit to my auto tranny?or some straight-flow mid box or bullet more better?


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but my car stated there vdo..what mean?and i know if i remove car battery -ve terminal and after plug back and start my car i found that engine very sluggish,rpm not stabil....and need to send back sc for re-tuning back...

anyone can clarify this?is it better to remove car battery?

my car is waja 4g18p 2002year..

what purpose actually we go to sc reset our ECU?they will check for error code..then what they will do?just reset to factory setting?

or can adjust..AF ratio or what?

oh mean..if now i remove my-ve battery,then after awhile it will feel unstabil or sluggish,or will died off engine..then after awhile it will self relearn ah?

any car also same?my waja 4g18 can also?